McComsey, D., et al., in US Patent Publication 2006/0041008 A1, published Feb. 23, 2006 disclose sulfamide derivatives of the following formula

useful for the treatment of epilepsy and related disorders. McComsey et al., further disclose a process for the preparation of sulfamide derivatives, including the process shown below

where a compound of formula (B) is reacted with sulfamide; in an organic solvent such as THF, dioxane, and the like; preferably at an elevated temperature in the range of about 50° C. to about 100° C., more preferably at about reflux temperature; to yield the corresponding compound of formula (A).
Abdel-Magid, A., et al., in US Patent Publication 2009/0247617 A1, Sep. 26, 2009 disclose a process for the preparation of sulfamide derivatives, as shown below

where a suitably substituted compound of formula (B), is reacted with a nitrogen protected compound of formula (C) (wherein —C(O)OR0 is a nitrogen protecting group, for example, an alkoxycarbonyl, aryloxycarbonyl, aralkyloxycarbonyl, and the like); in the presence of an organic or inorganic base; in an aprotic organic solvent; to yield the intermediate compound of formula (D), which is then de-protected according to known methods to yield the corresponding compound of formula (A).
Ballentine, s., et al., in US Patent Publication 2009/0247618 A1, Sep. 26, 2009 disclose a process for the preparation of sulfamide derivatives as shown below

where a suitably substituted compound of formula (B) is reacted with sulfamide; in an organic solvent such as THF, dioxane, and the like; preferably at an elevated temperature in the range of about 50° C. to about 100° C., more preferably at about reflux temperature; to yield the corresponding compound of formula (A).
There remains a need for processes for the preparation of compounds of formula (I), and more particularly the compound of formula (I-S), as hereinafter defined, which are suitably for large scale manufacture and/or preparation of both cold and isotope-labeled compounds.